Demos

Three small playgrounds. Everything runs from prepared examples — no code is executed.

Trace a web request

Step through what happens between typing an address and seeing a page.

  1. 1You type the address

  2. 2DNS lookup

  3. 3Secure connection

  4. 4Request sent

  5. 5Server responds

  6. 6Extra files fetched

  7. 7Page rendered

Who does what?

Sort each job into frontend, backend or database.

  • Show a spinner while an order saves

  • Check the user is allowed to issue a refund

  • Store every order permanently

  • Stack cards on a narrow phone screen

  • Calculate tax before charging a card

  • Find all orders above ₹5000 last month

Predict the output

Read the code and guess what it prints. Puzzle 1 of 3.

let count = 2;
count = count + 3;
console.log("Items: " + count);